Trailer tank assemblage



Nov. 17, 1936. F. G. THwAlTs TRAILER TANK ASSEMB/LAGE Filed May l5, 1935 2 Sheets-Sheet' l INVENTOR. @Zww/ BY M JM/SYM ATTORNEY.

Nov. 17, 1936. F. G. THwAlTs TRAILER TNK ASSEMBLAGE 2 Sheets-Sheet 2 Filed May l5, 1935 INVENTOR.

ATTORNEY.

Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE TRAILER TAN K AS SElVIBLAGE Frederick G. Thwaits, Wauwatosa, Wis., assigner to The Heil Co., Milwaukee, Wis., a corporation of Wisconsin The present invention relates in general to an improvement in the art of transportation, and relates more specically to an improved trailer tank assemblage for conveying liquids in bulk over highways, with the aid of a motor truck or the like Generally defined, an object of the invention is to provide a new and useful trailer tank assemblage which is simple and compact in construction, and which is moreover highly effective in actual use.

It has heretofore been common practice to provide so-called semi-trailer tanks for transporting liquids such as oil over the open highways. These prior semi-trailer tank assemblages usually consist essentially of an elongated tank having drainage piping at the bottom thereof and a forward end of reduced height, transporting wheels disposed beneath the rear portion of the tank, and a fth-wheel attachment located beneath the forward reduced portion of the tank, the fth-wheel attachment being cooperable with a complementary fifth-wheel element associated with the rear portion of the haulage truck.

In most of these prior semi-trailer assemblages, the lower porton of a relatively light single or multiple compartment tank, rests upon a relatively heavy undercarriage comprising supporting beams extending longitudinally beneath the tank and secured thereto, and trailer wheels and a fifth-Wheel element attached directly to the supporting beams. This type of construction not only necessitated undesirable elevation of the tank and obstruction to the bottom drains thereof, but also resulted in a relatively heavy and bulky assemblage which introduced many manufacturing diiiculties, since the tanks and the undercarriages for these semi-trailers are ordinarily built by different manufacturers, each specializing in the particular line of manufacture to which its contributory portion of the assemblage pertains.

While it has also heretofore been proposed to obviate some of these diculties by attaching the trailer wheels and a fifth-wheel assemblage directly to the tank and by reenforcing the tank structure suiciently to enable the same to sustain the load and to act as a draft member, thus eliminating the undercarriage structure entirely, this modified type of construction necessitates provision of a relatively bulky, heavy, and costly tank structure which is not suciently protected against possible damage. The modified assemblage moreover does not eliminate obstruction at the bottom of the tank, suciently to avoid interference with the drainage piping, and practically necessitates construction of the complete unit, by the tank manufacturer.

It is therefore a specic object of the present invention to provide an improved semi-trailer tank assemblage which will eliminate all of the objectionable features inherent in the above described types of semi-trailer tank assemblages.

Another specific object of the invention is to 10 provide a trailer-tank structure of relatively light but durable construction having minimum overall height and maximum storage capacity.

A further specic object of the invention is to provide a tank trailer unit comprising a tank and 15 a supporting and protecting cradle, which can be readily manufactured at moderate cost, and wherein the bottom of the tank is maintained free for attachment of drainage piping or the like.

Still another specic object of the invention is to provide a composite vehicular tank assembly comprising a transporting cradle and a tank structure detachably associated with the cradle, wherein the carrying frame and tank may either be produced by the same or independent manufacturers, and the unit may be readily assembled or dismantled.

An additional specific object of the present invention is to provide a trailer and tank assemblage, in which the trailer carriage serves primarily as a draft member for the assemblage, while the tank structure is suiciently reenforced to act as a beam member for carrying the variable load, thereby producing a compact but extremely strong transporting unit.

Another specific object of the invention is to provide an effective tank carriage which may be conveniently constructed of standard structural elements such as channel and angle beams, to produce an assemblage which will meet the requirements of the various traic and highway laws as to minimum or maximum lengths and widths of road vehicles.

These and other specific objects and advantages will be apparent from the following detailed description.

A clear conception of several specic embodiments of the invention, and of the mode of constructing and of utilizing Semi-trailer tank vehicles built in accordance with the improvement, may be had by referring to the drawings accompanyng and forming a part of this specification in which like reference characters designate the same or similar parts in the various views.

Fig. 4 is a somewhat enlarged transverse vertical section through the improved semi-trailer tank assemblage, showing the rearI of the haulage truck in dot-and-das'h, the section being taken along the line 4 4 of Fig. l, and also of Fig. 5;

Fig. 5 is a side elevation of anothertype of the improved semi-trailer tank assemblages providedv with single trailer wheels; and

Fig. 6is-'a top-view of the cradle of the semi- -trailer assemblage shown in Fig, 5, showing some -of thetank boundarylines in dot-and-dash lines. While the inventionhas been specifically shown Vand described herein', as being embodied in semitrailer tank assemblages adapted to be drawn 'through a standard fifth-wheel mechanism by a motor truck,v the semi-trailers in each case comprising separable tank and cradle members of particular types, itis not the intent to unnecessarily restrict the scope by such specific embodiments, since some of the improvedfeatures may obv-iou'slyfbe more generally applicable.4

Referring to'Figs. 1 to 4 inclusive of the drawings, the tandem wheel type of semi-trailer tank `vehicle disclosed therein, comprises in general, a `vehicular frame or cradle 8 forminga saddle; an elongated tank Sadapted to set within the saddle produced by the cradle 8; rear sets ofv tandem trailer wheels III carried by the cradle 8; and .a .front fifth-Wheel attachmentA I I carried either vbyl the cradle 8 or by the tank 9, or by both, beneath the forward reduced portion I2 of the tank.

The framelor cradle 8 is of relatively light structure zacting primarily as a draftmember for imparting motion fromthe haulage tractor or truck I3'to the supporting wheels I0, and vmay be constructed almost entirely of standard structural Yelements such as channel,` angle and flat bar stock, properly formed and welded or riveted together. As vspecifically shown, thetank receiving cradlek 8 comprises a continuous substantially horizontal upper channelmember I4 adapted to snugly Yembrace the medial portion ofthe tank 9, a series of threetransverse saddle beams I5 rigidly connecting the rearportions of the oppositesides of the lmember I4, and .another series of transverse slightlydished straightbeams IB likewise rigidly interconnectingl the front portions Vof the opposite sides of the upper member I4. In very long tank assemblages, one-,or more relatively light intermediate cross-braces I'I may also bel'provided, for the purpose of preventingv undesirable spreading of the central portions of the sides of the member I4, and the rear saddle beams I 5Y may be interconnected by a pair of lower beams *I8 which coact with the wheels I0 through` leaf springs I9, and which also v serveV as a support for -the rear bumper 2li.rv es previously indicated, the cradle frame should have suflicient strength to sustain the draft load, Without subjecting the -tanlf to undesirable longitudinal pull. f

The tank 9: may be of kthe single or multiple compartment type, eachl compartment ordinarily Pegg. Prende@ with'. an. .upper `.mfmhole 2 l.. and

I uponthe straight beams I6.

lower portion of the tank 9 may also bear against AWheels- I9 andthe `haulage truck I3. ouslyf indicated, -the upper" channel member I 4 of with lower fluid dispensing piping, not shown, which may extend either laterally or longitudinally beneath the tank in a well known manner. The interior of the tank 9 is preferably reenforced by means of tubular braces 22 and internal peripheral channel bars 23, suiiiciently to enable the completed tank structure to carry the entire beam load resulting from the weight of the tank and itscontents. Y l

The rear lower and opposite side portions of the tank 9, are cut away to clear the tandem supporting wheels I0, and the rear end of the reenforced tank rests upon the saddle beams I5 while the front reduced end I2 of the tank rests While the medial the cross-braces I'I, the tank structure should not necessarily depend upon these cross-braces for normal support, and the greater portion of the load should preferably be carriedl directly by the VAs previshown. in .thendrawinga or tothe lower face of thezreducedltank portion..l2, or to` both of these elements, and. ordinarily coaots with a lower fth-Wheelelement v26 .carried by the rear portionzo'f the truck -I3lto complete the fth wheel .l Vassemblage;4 In some *.cases, the upper and lower `fifth-wheel elements are disconnectible, and if so, thesemi-trailer tank structure, or the cradle 8,..should be provided'with a prop mechanism 21 of well known construction which is adaptedk vIso-sustain the` forwardportion of. the cradle 8 and .tank 9 when the truck YI3 is withdrawn from beneath thev reduced tank portion I2.

- Referring more specically'to Figs. 4 to 6 inclusive ofthe' drawings, the single wheel-set type of semi-trailer .disclosed therein, is quite similar to that previously described, and comprises a frame or cradle 8f forming an upwardly open saddle; a. somewhat shorter elongated. tank. 9

adapted to 'setwithin the vframe saddle; .a set of coaxial wheels III carried by the rearportion .of the cradle'll; and a frontfth-wheel element or attachment `II associated with' either the cradle l8', orwithlthetank 9. ,.or with both of these elements, beneath the forwardl reduced portion I2 The cradle 8 may also be formedof standard structural elements, and comprisesan'upper contin-uou's channel lmember IfI'; a pair of saddle beamsV I5 at the rearfof the member I4; and a series ofslightly dished straight'beam's I6 at the front of the member I 4. This cradle structure may again be provided with a cross-brace Il, and

ythe krear saddle beams vIE may likewise be intery connected kby lower beams I8 which. coact lwith the. wheels .Illfthrough leaf springs .I 9, and which also provide a support for a bumper 20. In this embodiment the cradle 8' may. again be of relatively. light. structure. .but .Should .be sufficiently strong to sustain the draft load without distortion.

The tank 9 may also be of the single or multiple compartment type, and each of the tank cornpartments has an upper manhole 2| and a lower fluid dispensing pipe of ordinary construction disposed either laterally or longitudinally beneath the tank. The interior of the tank El is likewise reenforced by braces 22 and bars 23 so as to enable the tank itself to sustain the entire beam load produced by the weight of the tank and its contents. The rear lower side portions of the tank 9 are also out away to provide wheel clearance, and the rear portion of the reenforced tank rests upon the beams I5 while the front reduced portion I2 rests upon the beams i6. The tank 9 `is thus supported primarily at its front and rear ends, and while the tank SH may bear against the cross-brace Il, it does not depend upon this brace for its major support. The tank 9 besides snugly fitting the upper channel member I4, may be detachably secured to this member by means of side angle irons 24 attached to the tank and clamped against the member M by bolts 25.

The fifth-wheel mechanism of the modied structure shown in Figs. 5 and 6, may be identical with that of Figs. 1 to 4 inclusive, and the tank 9' may also be provided with a prop 27 such as shown in Fig. 1.

From the foregoing description it will be apparent that the present invention provides a simple and relatively light semi-trailer assemblage comprising a reenforced tank and a cradle carriage therefor, wherein the tank may be disposed as near to the ground as possible while maintaining the lower portion thereof entirely free for the attachment of fluid dispensing piping and dispensing valve control mechanisms. The tank carrying cradle may be formed of structural steel members, and serves primarily as a draft rigging coacting with the front and rear heads of the tank for transmitting motion to the rear supportting wheels of the semi-trailer from the fifth wheel assemblage. The tank is sufciently reenforced to permit the same to carry the beam loads, and rests primarily directly upon the rear wheels and upon the rear portion of the haulage truck I3. By providing a tank which is separable from its carriage' or cradle, the tank may be readily manufactured by one manufacturer, while the cradle may be manufactured by an independent manufacturer, but both of the composite elements of the assemblage may obviously be built by the same manufacturer. The continuous upper beam member I4 will effectively prevent lateral or longitudinal v displacement of the tank during normal transportation thereof, and will also protect the opposite sides of the tank against damage by impact. The improved construction also permits formation of the tank of maximum width permissible under the highway laws of various States, and the length of the tank may be varied to suit Various conditions, thereby enabling the manufacturer to readily meet the requirements of the highway laws of various communities. The improved semi-trailer tank assemblage obviously eliminates all of the objectionable features inherent in the prior art structures specically referred to herein, and provides a unit which is relatively light but durable in construction, having minimum overall dimensions for maximum storage capacity.

It should be understood that it is not desired to limit the invention to the exact details of construction herein shown and described, for various modifications within the scope of the claims may occur to persons skilled in the art.

It is claimed and desired to secure by Letters Patent:-

1. A semi-trailer tank vehicle, comprising, a cradle frame consisting of a continuous substantially horizontal upper beam and front and rear lower transverse supporting beams connecting the sides of said upper beam, a tank mounted within said cradle frame with its front and rear ends engageable with the front and rear portions of said upper beam and resting primarily upon said transverse beams, trailer wheels coacting with said rear transverse beams, and a fifth-wheel element coacting with said front transverse beams beneath a reduced forward portion of the tank.

2. A semi-trailer tank vehicle, comprising, a cradle frame consisting of a continuous upper beam and rear transverse beams forming a saddle, a tank embraced by and engageable at its opposite ends directly with said upper beam and lying in a common plane and resting within said saddle, said tank having a front portion of reduced height remote from said saddle and terminating at its bottom substantially in said plane, a fifth-wheel element coacting with the vehicle beneath said reduced tank portion, and trailer wheels coacting with the vehicle at said saddle.

3. A semi-trailer tank vehicle, comprising, a draft frame consisting of a continuous upper channel beam and rear lower transverse beams forming a saddle, an internally reenforced tank completely surrounded and snugly embraced by said upper beam and resting upon said saddle beams, said tank having a front portion of reduced height supported upon the forward portion of said upper beam, fifth-wheel structure coacting with the vehicle beneath said reduced tank portion, and supporting wheels for the Vehicle carried by said saddle beams.

4. A semi-trailer tank vehicle, comprising, a frame having side draft and extreme end beams interconnected at their front and rear portions by transverse lower beams, an elongated tank mounted between said draft and end beams and having front and rear portions resting respectively upon said transverse lower beams, wheels carried by said rear transverse lower beams, a fifth-wheel element coacting with the vehicle near said front transverse lower beams, and means for detachably connecting the opposite sides of said tank to said draft beams with the tank ends engaging said end beams.

5. A semi-trailer tank vehicle, comprising, a cradle frame including a substantially continuous horizontal beam and front and rear transverse beams connecting the opposite sides of said horizontal beam, a tank snugly confined within said cradle frame with its front and rear ends engageable with the front and rear portions of said horizontal beam and resting primarily upon said transverse beams, trailer wheels coacting with said rear transverse beams, and a fifthwheel element coacting with said front transverse beams beneath a reduced forward portion of the tank.

6. A semi-trailer tank Vehicle, comprising, a cradle frame including a substantially continuous horizontal beam and front and rear transverse beams connecting the opposite sides of said horizontal beam, a tank snugly confined within said cradle frame with its front and rear ends engageable with the front and rear portions of said horizontal beam and resting primarily upon said transverse beams, trailer wheels coacting with; said rear transverse beams, a fifth-Wheel element coacting with said front transverse beams beneath a reduced forward portion of the tank, and means for detachably connecting the sides of said tank directly tov the opposite sides of said continuous beam.

7. A semi-trailer tank vehicle, comprising, a luni-tary cradle frame includingr a continuons horizontal beam and front and rear transverse beams connecting the opposite sides of said continuous beam, said front beams being disposed considerably higher than said rear beams, a tank snugly confined Within said cradle frame With its front and rear ends 'engageable with the front and rear portions of said horizontal beam and restingV primarily upon said transverse beams, trailer wheels coacting With said rear transverse beams, and a fifth-Wheel element coacting with said front transverse beams beneath, a reduced forward portion of the tank.

8'. A semi-trailer tank vehicle, comprising, a unitary cradle fname including a continuous horizontal beam and front and rear transverse l beams connecting the opposite sides of said continuous beam, said front beams being disposed considerably higher than said rear beams, a tank snugly confined Within said cradle frame with its front and rear ends engageable with the front and rear portions of said horizontal beam and resting primarily upon said transverse beams, trailer wheels coacting With said rear transverse beams, a fifth-wheel element coacting with said front transverse beams beneath a reduced for- Ward portion of the tank, and means for detachably connecting the sides of said tank directly to the opposite sides of said continuous beam.

FREDERICK G. THWAITS. 

